The invention relates to an electrical installation, notably a high voltage metalclad substation, having a metal enclosure, filled with a high dielectric strength gas, and subdivided into different compartments by tight insulating partitions.
A metalclad substation of the kind mentioned is made by assembling standard component parts, such as isolating switches, busbars and circuit breakers, each component being housed in a tight compartment. The partitioning limits the risk of an electric arc spreading from one compartment to the other and makes maintenance and repair operations easier, because only the part affected by the fault is opened to the atmosphere and disassembled. Housing each component in an individual compartment requires a large volume and is relatively costly. It has already been proposed to incorporate several functions in a single compartment but this simplification is prejudicial to the ease of carrying out operations on the substation. When an isolating switch is changed between two switch bays in the busbar, the two adjoining switch bays have to be switched off.
The object of the present invention is to achieve a simplified metalclad substation of reduced dimensions preserving the possibilities of performing operations on part of the substation, while the other part remains live.